The invention relates to a remote control device for a TV set comprising several program selection keys and an infrared transmitter circuit which radiates signals from operated keys to the TV set.
Such remote control devices are known. On such a TV set an indicating display is often provided next to the kinescope, showing the program selection chosen by the remote control device.
There are also TV sets known wherein a picture of another program can be mixed into the picture of a current program. Such a TV set is equipped with two tuners, the first tuner receiving the video and audio signals of the main program received and the second tuner only the videosignals of another program. Both tuners are controlled by the same program storage. Such a TV set is described in the ITT brochure "IC-set for picture within a picture", No. 6521-117-3D, April 1978.
It was also proposed to divide the picture of the TV set into four, nine or sixteen areas of the same size with each of these areas; one of the programs being selected shown in the form of permanently renewing still pictures (cf. catalog of the firm SONY, program 88/89, p. 23). In this case the tuner receives the programs provided in the program storage one after the other, reduces the picture contents, digitizes this and deposits the picture gained thereby in a storage unit. After digitalization the pictures appear on the corresponding area of the screen of the TV set. For example, every 2 to 5 seconds new pictures appear from the programs. A simultaneous, uninterrupted watching of a program, i.e. watching without still pictures, is impossible.
Often liquid crystal displays are used for small screens of TV sets. In these sets there are thin-film transistors between glass panes or non-linear elements for selecting the individual picture elements. Such liquid crystal displays are described in Peter M. Knoll, Displays Introduction in the technique of active and passive displays, Dr. Alfred Huthig-Verlag, Heidelberg, 1986, p. 216-220.
In the German application OS-33 22 729 a remote control device is described that comprises a transmitter in addition to a receiver. By a signal of the TV set the remote control device is switched onto standby status. Operation readiness is shown.